Diaporthales » Cytosporaceae » Cytospora

Cytospora galegicola

Cytospora galegicola Q.J. Shang, E. Camporesi & K.D. Hyde, in Shang, Hyde, Camporesi, Maharachchikumbura, Norphanphoun, Brooks & Liu, Mycosphere 11(1): 206 (2020)

Index Fungorum number: IF 555503; Facesofungi number: FoF 05100

Etymology – Names reflect the host, of which the fungus was collected from “Galega officinalis”.

Holotype – MFLU 16-2280

Saprobic on the bark. Sexual morph: Stromata 0.6–1.3 mm wide, with the poorly developed interior, solitary to gregarious, immersed, becoming raised to erumpent by the ostiolar canal, dark brown to black, glabrous, irregular in shape, arranged with conspicuous, scattered, roundish to cylindrical prominent ostioles. Ascomata (excluding necks) 170–275 μm high, 210–390 µm diam. (x̄ = 223 × 300 μm, n = 20), perithecial, immersed in a stroma, yellow to brown, globose to subglobose, glabrous, individual ostiole with the neck. Ostiolar canal 170–210 μm high, 40–135 μm diam. (x̄ = 189 × 44 μm, n = 18), cylindrical, sulcate, concentrated, periphysate. Peridium 23–34 μm wide, composed of two section layers, outer section comprising 3–6 layers, of relatively small, yellow, thick–walled cells, arranged in textura angularis, inner part comprising 3–4 layers of hyaline cells of textura angularis. Hamathecium composed of 5–6 μm wide, dense, cylindrical, septate, hyaline, paraphyses. Asci (33–)38–45(–49) × (4.5–)5.5–6.5(–7.5) μm (x̄ = 41 × 6 μm, n = 45), 8-spored, unitunicate, clavate, with short stalks, apically rounded to truncate, with a J- apical ring. Ascospores (5.8–)6.8–10(–12.5) × (1.5–)2–3(–4) μm (x̄ = 8.4 × 2.5 μm, n = 75), overlapping 1–2-seriate, hyaline, oblong to allantoid, aseptate, smooth-walled. Asexual morph: Coelomycetous. Conidiomata 430–589 μm, pycnidial, with multi-loculate, appearing as brown to black, watery, rounded, conidial masses, superficial, solitary or aggregated, subglobose, shiny, with white to brown mycelium covering the surface. Pycnidial walls 13–21 μm wide, comprising several layers of hyaline to brown, compressed hyphae, arranged in a textura intricata. Conidiogenous cells (7.2–)9.5–19.5(–23) × (1.5–)1.8–3.2(–4) (x̄ = 14.4 × 2.5 μm, n = 15), cylindrical to clavate, holoblastic, straight or curved. Conidia (4.8–)5–6.8(–10.7) × (0.8–)1–1.5(–2.0) (x̄ = 7.6 × 1.3 μm, n = 150), hyaline, allantoid, some with strongly curved ends, unicellular, smooth-walled.

Culture characteristics: Ascospores germinating on PDA within 24 hrs. Germ tubes produced from all sides. Colonies on PDA reaching 5–5.5 cm diam. after 15 days at room temperature, colonies circular to irregular, medium dense, flat or effuse, slightly raised, with edge fimbriate, fluffy to fairy fluffy, white from above, light yellow from below; not producing pigments in agar.

Material examined: Italy, Fiumicello, Premilcuore (Province of Forlì-Cesena [FC]), on dead aerial stem of Galega officinalis (Fabaceae), 27 July 2016, E. Camporesi, IT 3045 (MFLU 16-2280, holotype; KUN-HKAS 100884, isotype), ex-type living culture, MFLUCC 18-1199.

Notes: The phylogenetic inference obtained in this study of Shang et al. (2020) shows that the new taxon Cytospora galegicola (MFLUCC 18-1199) forms a distinct lineage close to Cytospora coenobitica (CBS 283.74) and Cytospora subclypeata (CBS 117.67) with high support (ITS, 96% ML, 80% MPand 1.00 PP). Morphologically, Cytospora galegicola has larger conidia than C. coenobitica and C. subclypeata (Saccardo 1884, 1986). Therefore, Cytospora galegicola is described as a new species and the description and illustration of the holomorph are provided herein.